U.S. patent application number 12/814582 was filed with the patent office on 2010-12-16 for course evaluation apparatus and course evaluation method.
This patent application is currently assigned to Toyota Jidosha Kabushiki Kaisha. Invention is credited to Kazuaki Aso, Toshiki Kindo, Katsuhiro Sakai.
Application Number | 20100318240 12/814582 |
Document ID | / |
Family ID | 43307114 |
Filed Date | 2010-12-16 |
United States Patent
Application |
20100318240 |
Kind Code |
A1 |
Kindo; Toshiki ; et
al. |
December 16, 2010 |
COURSE EVALUATION APPARATUS AND COURSE EVALUATION METHOD
Abstract
A course evaluation that evaluates a course of a mobile unit
includes: generating a predetermined first course of the mobile
unit; generating, for the first course, a second course for which a
controlled amount of the mobile unit after a predetermined driving
condition is satisfied is increased as compared with a controlled
amount of the mobile unit on the first course; estimating another
object course, which is a course of another object; determining
whether the second course interferes with the other object course;
and evaluating a degree of safety of the first course on the basis
of a result of determination as to whether the second course
interferes with the other object course.
Inventors: |
Kindo; Toshiki;
(Yokohama-shi, JP) ; Aso; Kazuaki; (Susono-shi,
JP) ; Sakai; Katsuhiro; (Hadano-shi, JP) |
Correspondence
Address: |
GIFFORD, KRASS, SPRINKLE,ANDERSON & CITKOWSKI, P.C
PO BOX 7021
TROY
MI
48007-7021
US
|
Assignee: |
Toyota Jidosha Kabushiki
Kaisha
Toyota-Shi
JP
|
Family ID: |
43307114 |
Appl. No.: |
12/814582 |
Filed: |
June 14, 2010 |
Current U.S.
Class: |
701/1 |
Current CPC
Class: |
G08G 1/166 20130101 |
Class at
Publication: |
701/1 |
International
Class: |
G08G 1/16 20060101
G08G001/16; G06F 7/00 20060101 G06F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 12, 2009 |
JP |
JP2009-141084 |
Claims
1. A course evaluation apparatus that evaluates a course of a
mobile unit, comprising: a first course generation unit that
generates a predetermined first course of the mobile unit; a second
course generation unit that generates, for the first course, a
second course for which a controlled amount of the mobile unit
after a predetermined driving condition is satisfied is increased
as compared with a controlled amount of the mobile unit on the
first course; another object course estimation unit that estimates
another object course, which is a course of another object; an
interference determination unit that determines whether the second
course interferes with the other object course; and a safety
evaluation unit that evaluates a degree of safety of the first
course on the basis of a result of determination as to whether the
second course interferes with the other object course.
2. The course evaluation apparatus according to claim 1, wherein
the predetermined driving condition is at least one of a driving
time of the mobile unit and a driving distance of the mobile
unit.
3. The course evaluation apparatus according to claim 1, wherein
the controlled amount of the mobile unit includes at least one of a
deceleration of the mobile unit and a steering speed of the mobile
unit.
4. The course evaluation apparatus according to claim 1, wherein
the other object course estimation unit estimates a course, along
which the other object approaches the mobile unit, as the other
object course.
5. The course evaluation apparatus according to claim 4, further
comprising: another object maximum speed acquisition unit that
acquires another object maximum speed, which is a maximum speed
that the other object can travel at, wherein the other object
course estimation unit estimates a course, along which the other
object approaches the mobile unit at the other object maximum
speed, as the other object course.
6. The course evaluation apparatus according to claim 1, wherein
The controlled amount of the mobile unit on the second course is
increased as compared with a controlled amount of the mobile unit
on the first course after the predetermined driving condition is
satisfied.
7. The course evaluation apparatus according to claim 1, wherein
when the interference determination unit determines whether the
second course interferes with the other object course, it is
determined whether the second course intersects with the other
object course.
8. The course evaluation apparatus according to claim 7, wherein
the safety evaluation unit evaluates that the degree of safety of
the first course corresponding to the second course is high when it
is determined that the second course does not intersect with the
other object course, and evaluates that the degree of safety of the
first course corresponding to the second course is low when it is
determined that the second course intersects with the other object
course.
9. The course evaluation apparatus according to claim 1, wherein
the first course generation unit generates the first course
corresponding to each of a plurality of driving efficiencies.
10. The course evaluation apparatus according to claim 1, wherein
the second course generation unit generates a plurality of the
second courses, and the safety evaluation unit evaluates the degree
of safety of the first course on the basis of a result of
determination as to whether each of the plurality of second courses
interferes with the other object course.
11. The course evaluation apparatus according to claim 10, wherein
the first course generation unit generates the first course
corresponding to each of a plurality of driving efficiencies, and
the second course generation unit generates the second course
corresponding to each of the plurality of first courses.
12. The course evaluation apparatus according to claim 11, wherein
the safety evaluation unit evaluates that the degree of safety of
the first course corresponding to the second course is high when it
is determined that the second course does not intersect with the
other object course, evaluates that the degree of safety of the
first course corresponding to the second course is low when it is
determined that the second course intersects with the other object
course, and evaluates the first course, corresponding to a highest
driving efficiency among the first courses evaluated to have a high
degree of safety, as a course along which the mobile unit travels
when a plurality of the first courses are evaluated to have a high
degree of safety.
13. The course evaluation apparatus according to claim 1, wherein
the other object course estimation unit estimates a plurality of
the other object courses.
14. The course evaluation apparatus according to claim 1, wherein
the first course generation unit generates the first course on the
basis of a condition that the mobile unit travels in the middle of
a road at a speed limit.
15. A course evaluation method that evaluates a course of a mobile
unit, comprising: generating a predetermined first course of the
mobile unit; generating, for the first course, a second course for
which a controlled amount of the mobile unit after a predetermined
driving condition is satisfied is increased as compared with a
controlled amount of the mobile unit on the first course;
estimating another object course, which is a course of another
object; determining whether the second course interferes with the
other object course; and evaluating a degree of safety of the first
course on the basis of a result of determination as to whether the
second course interferes with the other object course.
16. The course evaluation method according to claim 15, wherein the
predetermined driving condition is at least one of a driving time
of the mobile unit and a driving distance of the mobile unit.
17. The course evaluation method according to claim 15, wherein the
controlled amount of the mobile unit includes at least one of a
deceleration of the mobile unit and a steering speed of the mobile
unit.
18. The course evaluation method according to claim 15, wherein a
course, along which the other object approaches the mobile unit, is
estimated as the other object course.
19. The course evaluation method according to claim 18, further
comprising: acquiring another object maximum speed, which is a
maximum speed that the other object can travel at, wherein a
course, along which the other object approaches the mobile unit at
the other object maximum speed, is estimated as the other object
course.
20. The course evaluation method according to claim 15, wherein a
plurality of the second courses are generated, and the degree of
safety of the first course is evaluated on the basis of a result of
determination as to whether each of the plurality of second courses
interferes with the other object course.
Description
RELATED APPLICATION
[0001] This application claims priority to Japanese Patent
Application No. 2009-141084 filed on Jun. 12, 2009, which is
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a course evaluation apparatus and
course evaluation method that evaluate a course generated and, more
particularly, to a course evaluation apparatus and course
evaluation method that evaluate a course of a mobile unit, such as
a vehicle.
[0004] 2. Description of the Related Art
[0005] In an existing art, a course setting apparatus is known as a
course evaluation apparatus that evaluates a course of a mobile
unit (see, for example, Japanese Patent Application Publication No.
2007-230454 (JP-A-2007-230454)). The course setting apparatus
evaluates courses along which a specific object included in a
plurality of objects can travel, and then sets a course of the
specific object. In the course setting apparatus, changes in
positions, at which the plurality of objects can be located over
time, are generated as trajectories on a time space constituted of
time and space. The trajectories are used to estimate courses of
the plurality of objects, and then the degrees of interference
between the courses along which the specific object can travel and
the courses along which the other objects can travel are
quantitatively calculated on the basis of the estimated courses of
the plurality of objects. After that, the course, along which the
specific object is least likely to interfere with the other
objects, is determined as an appropriate course for the specific
object.
[0006] However, in the course setting apparatus described in
JP-A-2007-230454, setting the course of the specific object
requires the fact that the course is least likely to cause
interference between the specific object and the other objects.
Therefore, this does not take into consideration, for example,
driving efficiency at the time when a mobile unit, which is the
specific object, travels. Thus, the driving efficiency of the
mobile unit may possibly be impaired despite little likelihood of
interference with the other objects.
SUMMARY OF THE INVENTION
[0007] The invention provides a course evaluation apparatus and
course evaluation method that allow a mobile unit to avoid
interference with another object with a high driving efficiency,
and that are able to evaluate a course of the mobile unit while
achieving both driving efficiency and interference avoidance.
[0008] A first aspect of the invention relates to a course
evaluation apparatus that evaluates a course of a mobile unit. The
course evaluation apparatus includes: a first course generation
unit that generates a predetermined first course of the mobile
unit; a second course generation unit that generates, for the first
course, a second course for which a controlled amount of the mobile
unit after a predetermined driving condition is satisfied is
increased as compared with a controlled amount of the mobile unit
on the first course; another object course estimation unit that
estimates another object course, which is a course of another
object; an interference determination unit that determines whether
the second course interferes with the other object course; and a
safety evaluation unit that evaluates a degree of safety of the
first course on the basis of a result of determination as to
whether the second course interferes with the other object
course.
[0009] When the degree of safety of the first course is evaluated
so as to employ a course that is less likely to cause interference
with another object, the evaluation is made so as not to employ,
for example, a course that can avoid interference with another
object when hard control is conducted on the mobile unit.
Therefore, it is forced to select a course of which the driving
efficiency of the mobile unit is low. In terms of this point, the
course evaluation apparatus according to the first aspect
generates, for the first course, the second course for which the
controlled amount of the mobile unit after a predetermined driving
condition is satisfied is increased as compared with that of the
first course, and estimates another object course, which is a
course of another object. Then, the degree of safety of the first
course is evaluated on the basis of the result of determination as
to whether the second course interferes with the other object
course. Therefore, even when the mobile unit is likely to interfere
with another object, the first course that can avoid the
interference when hard control is conducted in the second course
may be evaluated as a course that is less likely to cause
interference. Thus, it is possible to allow a mobile unit to avoid
interference with another object with a high driving efficiency,
and it is possible to evaluate a course of the mobile unit while
achieving both driving efficiency and interference avoidance.
[0010] In the first aspect, the predetermined driving condition may
be at least one of a driving time of the mobile unit and a driving
distance of the mobile unit.
[0011] In this way, a driving time or driving distance of the
mobile unit may be suitably used as the predetermined driving
condition.
[0012] In the first aspect, the controlled amount of the mobile
unit may include at least one of a deceleration of the mobile unit
and a steering speed of the mobile unit.
[0013] In this way, the deceleration or steering speed of the
mobile unit may be suitably used as the controlled amount of the
mobile unit.
[0014] In the first aspect, the other object course estimation unit
may estimate a course, along which the other object approaches the
mobile unit, as the other object course.
[0015] When another object travels along a course that approaches
the mobile unit, the mobile unit is highly likely to interfere with
the other object. Therefore, by estimating a course of another
object when the other object approaches the mobile unit as another
object course, it is possible to accurately evaluate a course that
avoids interference between the mobile unit and the other
object.
[0016] The first aspect may further include another object maximum
speed acquisition unit that acquires another object maximum speed,
which is a maximum speed that the other object can travel at. In
this case, the other object course estimation unit may estimate a
course, along which the other object approaches the mobile unit at
the other object maximum speed, as the other object course.
[0017] When the other object travels along a course along which the
other object approaches the mobile unit at the other object maximum
speed, the mobile unit is highly likely to interfere with the other
object. Therefore, by estimating a course of another object when
the other object approaches the mobile unit at a maximum speed as
another object course, it is possible to accurately evaluate a
course that avoids interference between the mobile unit and the
other object.
[0018] In the first aspect, the second course generation unit may
generate a plurality of the second courses, and the safety
evaluation unit may evaluate the degree of safety of the first
course on the basis of a result of determination as to whether each
of the plurality of second courses interferes with the other object
course.
[0019] In this way, the degree of safety of the first course is
evaluated on the basis of the result of determination as to whether
each of the plurality of second courses interferes with the other
object course. By so doing, it is possible to further accurately
determine the degree of safety of the first course.
[0020] A second aspect of the invention relates to a course
evaluation method that evaluates a course of a mobile unit. The
course evaluation method includes: generating a predetermined first
course of the mobile unit; generating, for the first course, a
second course for which a controlled amount of the mobile unit
after a predetermined driving condition is satisfied is increased
as compared with a controlled amount of the mobile unit on the
first course; estimating another object course, which is a course
of another object; determining whether the second course interferes
with the other object course; and evaluating a degree of safety of
the first course on the basis of a result of determination as to
whether the second course interferes with the other object
course.
[0021] With the course evaluation apparatus and the course
evaluation method according to the aspects of the invention, a
mobile unit is able to avoid interference with another object with
a high driving efficiency, and it is possible to evaluate a course
of the mobile unit while achieving both driving efficiency and
interference avoidance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The foregoing and further objects, features and advantages
of the invention will become apparent from the following
description of example embodiments with reference to the
accompanying drawings, wherein like numerals are used to represent
like elements and wherein:
[0023] FIG. 1 is a block diagram of a course evaluation apparatus
according to an embodiment of the invention;
[0024] FIG. 2 is a view that illustrates generation of estimated
courses in the course evaluation apparatus according to the
embodiment of the invention;
[0025] FIG. 3 is a flowchart that shows the procedure executed by
the course evaluation apparatus according to the embodiment of the
invention; and
[0026] FIG. 4 is a view that illustrates the relationship between
the estimated courses and a pedestrian approaching course according
to the embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0027] Hereinafter, an embodiment of the invention will be
described with reference to the accompanying drawings. Note that
like reference numerals denote the same components in the
description of the drawings, and the overlap description is
omitted. In addition, for the sake of easy illustration, the ratios
of the dimensions of the drawings do not always coincide with those
of the description.
[0028] A course evaluation apparatus according to the present
embodiment is provided for a vehicle that carries out automatic
cruising. In this automatic cruising, for example, an environment
around a host vehicle is detected to determine an optimal course
for driving the host vehicle, and then vehicle control, such as
acceleration/deceleration control and steering control, is executed
so that the host vehicle travels along the determined course.
[0029] In the course evaluation apparatus, a plurality of estimated
courses are generated, the degree of safety of each course is
evaluated, and then a course evaluated to have the highest degree
of safety is determined as the course along which the host vehicle
travels. The vehicle equipped with the course evaluation apparatus
carries out automatic cruising on the basis of control signals
transmitted from the course evaluation apparatus to a drive control
unit and steering control unit of the vehicle.
[0030] As shown in FIG. 1, the course evaluation apparatus
according to the present embodiment includes a course evaluation
electronic control unit (ECU) 1. A driving information acquisition
unit 2 and a course information output unit 3 are connected to the
course evaluation ECU 1.
[0031] The course evaluation ECU 1 is, for example, mainly formed
of a computer that includes a central processing unit (CPU), a read
only memory (ROM) and a random access memory (RAM). In addition,
the course evaluation ECU 1 includes a course generation unit 11, a
braking course generation unit 12, a pedestrian approaching
behavior calculation unit 13, a braking course evaluation unit 14
and a course evaluation unit 15. The course generation unit 11
serves as a first course generation unit. The braking course
generation unit 12 serves as a second course generation unit. The
pedestrian approaching behavior calculation unit 13 serves as
another object course estimation unit. The braking course
evaluation unit 14 serves as an interference determination unit.
The course evaluation unit 15 serves as a safety evaluation
unit.
[0032] The driving information acquisition unit 2 acquires driving
information that includes vehicle driving information, such as the
speed and steered angle of the vehicle, surrounding information
obtained by sensing the positions, speeds, and the like, of objects
and/or other vehicles around the vehicle, and driving road
information, such as a map. The driving information acquisition
unit 2, for example, acquires driving information in such a manner
that signals of sensors and navigation system that are installed in
the vehicle are input to the driving information acquisition unit
2. The driving information acquisition unit 2 transmits the
acquired driving information to the course evaluation ECU 1.
[0033] The course generation unit 11 of the course evaluation ECU 1
generates a plurality of estimated courses of the host vehicle on
the basis of information of a shape, or the like, of a road around
the host vehicle, included in the driving information transmitted
from the driving information acquisition unit 2. The course
generation unit 11 outputs host vehicle course signals,
corresponding to the plurality of generated estimated courses of
the host vehicle, to the braking course generation unit 12 and the
course evaluation unit 15.
[0034] The braking course generation unit 12 generates braking
courses of the host vehicle on the basis of the host vehicle course
signals output from the course generation unit 11. Here, the
braking course means a course along which the host vehicle travels
when applying brakes with a maximum braking force after a
predetermined period of time has elapsed from a current time. The
braking course generation unit 12 generates respective braking
courses for the plurality of estimated courses of the host vehicle.
The braking course generation unit 12 outputs braking course
signals, corresponding to the generated braking courses, to the
braking course evaluation unit 14.
[0035] For example, in the course generation unit 11, as shown in
FIG. 2, the location of a vehicle M is set as a starting point, and
then a plurality of, for example, three, estimated courses P1 to P3
from the starting point are generated. The order of decreasing
driving efficiency of these three estimated courses is the first
estimated course P1, the second estimated course P2 and the third
estimated course P3.
[0036] Here, the first estimated course P1 is formed of a first
immediate course p11 up to a lapse of a predetermined period of
time and a first succeeding course p12 after the lapse of the
predetermined period of time. In addition, the second estimated
course P2 is formed of a second immediate course p21 up to a lapse
of the predetermined period of time and a second succeeding course
p22 after the lapse of the predetermined period of time.
Furthermore, the third estimated course P3 is formed of a third
immediate course p31 up to a lapse of the predetermined period of
time and a third succeeding course p32 after the lapse of the
predetermined period of time.
[0037] Subsequently, the braking course generation unit 12
generates a first braking course p13 following the first immediate
course p11 for the first estimated course P1. Similarly, the
braking course generation unit 12 generates a second braking course
p23 following the second immediate course p21 for the second
estimated course P2. Furthermore, the braking course generation
unit 12 generates a third braking course p33 following the third
immediate course p31 for the third estimated course P3. These
estimated courses P1 to P3 each correspond to a first course
according to the aspect of the invention. In addition, the braking
courses p13 to p33 each correspond to a second course according to
the aspect of the invention.
[0038] The pedestrian approaching behavior calculation unit 13
detects a pedestrian around the host vehicle on the basis of the
driving information transmitted from the driving information
acquisition unit 2. Furthermore, the pedestrian approaching
behavior calculation unit 13 estimates the behavior of the detected
pedestrian and then calculates a pedestrian approaching behavior,
which is a behavior of the pedestrian approaching the host
vehicle.
[0039] Here, the pedestrian approaching behavior means a behavior
that is most likely to cause interference between the pedestrian
and the host vehicle among possible behaviors taken by the
pedestrian. An example of the pedestrian approaching behavior is a
behavior of a pedestrian approaching the host vehicle. Furthermore,
another example is a behavior of a pedestrian approaching the host
vehicle at a maximum speed assumed.
[0040] The pedestrian approaching behavior calculation unit 13
obtains a pedestrian approaching behavior course, which is a course
along which the pedestrian conducts the pedestrian approaching
behavior, on the basis of the calculated pedestrian approaching
behavior. The pedestrian approaching behavior calculation unit 13
outputs a pedestrian approaching behavior course signal,
corresponding to the obtained pedestrian approaching behavior
course, to the braking course evaluation unit 14.
[0041] The braking course evaluation unit 14 compares the
pedestrian approaching behavior course based on the pedestrian
approaching behavior course signal output from the pedestrian
approaching behavior calculation unit 13 with the braking courses
based on the braking course signals output from the braking course
generation unit 12, and then determines whether the pedestrian
approaching behavior course interferes with each of the braking
courses. The braking course evaluation unit 14 generates a braking
evaluation value on the basis of the result of determination as to
whether the pedestrian approaching behavior course interferes with
each of the braking courses. The braking course evaluation unit 14
outputs braking evaluation signals, corresponding to the generated
braking evaluation values, to the course evaluation unit 15.
[0042] The course evaluation unit 15 evaluates a plurality of
courses corresponding to the host vehicle course signals output
from the course generation unit 11 on the basis of the braking
evaluation value signals output from the braking course evaluation
unit 14. The course evaluation unit 15 determines the estimated
course having the highest braking evaluation value as the course of
the host vehicle as a result of evaluation of the plurality of
courses. The course evaluation unit 15 transmits a course
evaluation signal, corresponding to the determined course of the
host vehicle, to the course information output unit 3.
[0043] The course information output unit 3 selects a course, along
which the vehicle should travel, on the basis of the course
evaluation signal transmitted from the course evaluation ECU 1. The
course information output unit 3 transmits course information,
corresponding to the selected course, to the drive control unit,
steering control unit, and the like, of the vehicle.
[0044] Next, the procedure executed by the course evaluation
apparatus according to the present embodiment will be
described.
[0045] As shown in FIG. 3, in the course evaluation apparatus
according to the present embodiment, first, the course generation
unit 11 generates a plurality of estimated courses (S1). Estimated
courses are generated on the basis of driving information
transmitted from the driving information acquisition unit 2. After
the estimated courses are generated, the pedestrian approaching
behavior calculation unit 13 calculates a pedestrian approaching
course (S2). The pedestrian approaching course is calculated on the
basis of the driving information transmitted from the driving
information acquisition unit 2.
[0046] Subsequently, the braking course generation unit 12
generates braking courses on the basis of host vehicle course
signals output from the course generation unit 11 (S3). The braking
courses generated by the braking course generation unit 12 are
courses along which the host vehicle travels when applying brakes
with maximum braking force after a predetermined period of time has
elapsed from a current time. Therefore, as shown in FIG. 2, the
first braking course p13 is shorter than the first succeeding
course p12. Similarly, the second braking course p23 and the third
braking course p33 are respectively shorter than the second
succeeding course p22 and the third succeeding course p32.
[0047] After the braking courses are generated, the braking course
evaluation unit 14 evaluates the braking courses (S4). In
evaluation of the braking courses, it is determined whether the
pedestrian approaching course interferes with each of the plurality
of braking courses. In the interference determination here, it is
determined whether the pedestrian approaching course intersects
with each of the plurality of braking courses. The degree of safety
of each of the braking courses is evaluated on the basis of the
result of determination as to whether the pedestrian approaching
course interferes with each of the plurality of braking
courses.
[0048] For example, specifically, as shown in FIG. 4, it is
determined whether a pedestrian approaching course Qw intersects
with each of the first braking course p13, second braking course
p23 and third braking course p33. In the example shown in FIG. 4,
it is determined that the pedestrian approaching course Qw
intersects with the first braking course p13, and does not
intersect with the second braking course p23 or the third braking
course p33.
[0049] Therefore, because the degree of safety of the first braking
course p13 is low, the braking evaluation value of the first
braking course p13 is set to a low evaluation value that indicates
a low degree of safety. In addition, because the degrees of safety
of both the second braking course p23 and the third braking course
p33 are high, the braking evaluation values of the second braking
course p23 and third braking course p33 are set to high evaluation
values that indicate a high degree of safety.
[0050] After the respective braking courses are evaluated in this
way, the course evaluation unit 15 sets the braking evaluation
values calculated by the braking course evaluation unit 14 as
course evaluation values of the estimated courses (S5). Therefore,
in the case of an example shown in FIG. 4, the evaluation of the
first estimated course P1 is low, and the evaluations of the second
estimated course P2 and the third estimated course P3 are high. The
course evaluation unit 15 evaluates and determines the second
estimated course P2 having a higher driving efficiency between the
second estimated course P2 and the third estimated course P3 that
are given high evaluations as a course along which the host vehicle
M travels, and then transmits a course evaluation signal to the
course information output unit 3. After that, the process executed
by the course evaluation apparatus ends.
[0051] In this way, as shown in FIG. 4, the course evaluation
apparatus according to the present embodiment generates the braking
courses p13 to p33 for which the braking amounts of the host
vehicle M after the predetermined period of time has elapsed are
increased as compared with those of the estimated courses P1 to P3,
and estimates the pedestrian approaching course Qw. Then, each of
the degrees of safety of the estimated courses P1 to P3 is
evaluated on the basis of the result of determination as to whether
a corresponding one of the braking courses p13 to p33 interferes
with the pedestrian approaching course Qw.
[0052] Here, for example, it is assumed that each of the degrees of
safety of the estimated courses P1 to P3 is evaluated on the basis
of determination as to whether each of the estimated courses P1 to
P3 interferes with the pedestrian approaching course Qw. In this
case, in the first estimated course P1 and the second estimated
course P2, it is highly likely to cause interference between a
pedestrian H and the host vehicle M, and in the third estimated
course P3 it is less likely to cause interference between the
pedestrian H and the host vehicle M. Therefore, the evaluations of
the first estimated course P1 and second estimated course P2 are
low, and the evaluation of the third estimated course P3 is
high.
[0053] However, when the pedestrian H conducts an approaching
behavior, which is a behavior that is highly likely to interfere
with the host vehicle M, if a course allows the host vehicle M to
avoid interference with the pedestrian H through hard braking, the
course is actually less likely to cause interference between the
pedestrian H and the host vehicle M.
[0054] Then, the course evaluation apparatus according to the
present embodiment evaluates the estimated courses P1 to P3 on the
basis of determination as to whether each of the braking courses
p13 to p33 interferes with the pedestrian approaching course Qw. In
this case, it is highly likely to cause interference between the
pedestrian H and the host vehicle M when the first estimated course
P1 is selected, and it is less likely to cause interference between
the pedestrian H and the host vehicle M when the second estimated
course P2 or the third estimated course P3 is selected. Therefore,
the evaluation of the first estimated course P1 is low, and the
evaluations of the second estimated course P2 and third estimated
course P3 are high.
[0055] Thus, when the estimated courses P1 to P3 are evaluated on
the basis of determination as to whether each of the estimated
courses P1 to P3 interferes with the pedestrian approaching course
Qw, only the evaluation of the third estimated course P3 is high;
whereas, when the estimated course P1 to P3 are evaluated on the
basis of determination as to whether each of the braking courses
p13 to p33 interferes with the pedestrian approaching course Qw,
the evaluation of the second estimated course P2 is also high in
addition to the third estimated course P3. Therefore, it is
possible to avoid interference between the host vehicle M and the
pedestrian H and also to give a high evaluation to the second
estimated course P2 having a high driving efficiency. Hence, the
host vehicle is allowed to avoid interference with the pedestrian
with a high driving efficiency, and it is possible to evaluate a
course of the host vehicle while achieving both driving efficiency
and interference avoidance.
[0056] The embodiment of the invention is described above; however,
the aspect of the invention is not limited to the above embodiment.
For example, in the above embodiment, the course evaluation
apparatus is provided for the vehicle that carries out automatic
cruising; instead, the course evaluation apparatus may be provided
for a vehicle driven by a driver. In this case, the driver may be
notified of an evaluated course through a monitor or a speaker.
[0057] In addition, in the above embodiment, three estimated
courses are generated and compared to evaluate each estimated
course; instead, a larger number of estimated courses may be
generated and evaluated. Furthermore, in the above embodiment, each
braking evaluation value is evaluated on two scales, that is, high
and low; instead, each braking evaluation value may be evaluated on
multiple number of scales over two scales. Alternatively, each
braking evaluation value may be evaluated not on a rating scale but
on a numerical scale. When each braking evaluation value is
evaluated on a rating scale or a numerical scale, the braking
evaluation value may be generated not only on the basis of whether
the pedestrian approaching course intersects with the corresponding
braking course but also on the basis of a degree of proximity, or
the like, between the pedestrian approaching course and the braking
course.
[0058] Furthermore, in the above embodiment, one braking course is
generated for each of the estimated courses P1 to P3; instead, a
plurality of two or more braking courses may be generated for each
of the estimated courses P1 to P3. When a plurality of braking
courses are generated for each estimated course, these plurality of
braking courses are compared with the pedestrian approaching course
to obtain a braking evaluation value to thereby make it possible to
evaluate the estimated course on the basis of the braking
evaluation value.
[0059] When a braking evaluation value is obtained from a plurality
of braking courses, for example, it is applicable that it is
determined whether the evaluation of an individual braking
evaluation value obtained through the result of comparison between
each braking course and the pedestrian approaching course is high
or low and then a braking evaluation value is generated in
accordance with the ratio of a high evaluation and a low
evaluation. Alternatively, it is also applicable that an individual
braking evaluation value is obtained on a rating scale or a
numerical scale through comparison between each braking course and
the pedestrian approaching course and then a braking evaluation
value is obtained through calculation, such as adding the
individual braking evaluation values.
[0060] In addition, in the above embodiment, the predetermined
driving condition is a driving time of the host vehicle; instead,
the predetermined driving condition may be, for example, another
condition, such as a driving distance of the host vehicle.
Furthermore, in the above embodiment, the controlled amount of the
mobile unit is a deceleration amount of the host vehicle; instead,
the controlled amount may be, for example, another controlled
amount, such as a steering amount of the host vehicle. Moreover, it
is also applicable that the controlled amount may be a combination
of a steering amount of the host vehicle and a deceleration amount
of the host vehicle.
[0061] Furthermore, in the above embodiment, the pedestrian is
illustrated as another object; instead, a mobile unit other than
the pedestrian may be another object. Specifically, another object
may be, for example, another vehicle or an animal other than a
human being.
[0062] In addition, in the above embodiment, the pedestrian
approaching course Qw is used as another object course; instead, it
is also applicable that another object course may be a course other
than the approaching course, that is, for example, a pedestrian
normal course Qr that extends across a lane, on which the host
vehicle M travels, substantially perpendicularly with respect to a
road as shown in FIG. 4. In this case, in comparison between the
pedestrian normal course Qr and the estimated courses P1 to P3,
only the evaluation of the first estimated course P1 is low, and
the evaluation s of the third estimated course P3 and second
estimated course P2 are high. In contrast, in comparison between
the pedestrian normal course Qr and the braking courses p13 to p33,
all the evaluations of the first estimated course P1 to third
estimated course P3 are high. Thus, it is possible to determine the
first estimated course P1, having a driving efficiency higher than
that of the second estimated course P2, as a course of the host
vehicle M. In addition, it is also applicable that another object
course may be not only the pedestrian approaching course Qw or the
pedestrian normal course Qr but also a pedestrian course between
the pedestrian approaching course Qw and the pedestrian normal
course Qr. In addition, the shape of another object course may be
estimated as not a linear but a shape having a curvature, a wave,
or the like.
[0063] Furthermore, in the above embodiment, one pedestrian
approaching course Qw is generated for each of the estimated
courses P1 to P3; instead, for example, it is also applicable that
a plurality of behaviors of the pedestrian are estimated and then a
plurality of pedestrian approaching courses are generated. Here,
when a plurality of pedestrian approaching courses are generated,
these plurality of pedestrian approaching courses are compared with
each braking course to obtain a braking evaluation value, and then
estimated courses may be evaluated on the basis of the
corresponding braking evaluation values.
[0064] When a braking evaluation value is obtained from a plurality
of pedestrian approaching courses for each estimated course, for
example, it is applicable that it is determined whether the
evaluation of an individual braking evaluation value obtained
through the result of comparison between each pedestrian
approaching course and the braking course is high or low and then a
braking evaluation value is generated in accordance with the ratio
of a high evaluation and a low evaluation. Alternatively, it is
also applicable that an individual braking evaluation value is
obtained on a rating scale or a numerical scale through comparison
between each pedestrian approaching course and the braking course
and then a braking evaluation value is obtained through
calculation, such as adding the individual braking evaluation
values.
[0065] In addition, in the above embodiment, the moving speed of
the pedestrian is not particularly considered; however, it is also
applicable that the moving speed of the pedestrian, or the like, is
considered. At this time, it is desirable to evaluate a course on
the assumption that another object is travelling at its maximum
speed. By evaluating a course on the assumption that the travelling
speed of another object is maximal, it is possible to estimate a
course of the other object, along which the other object reaches a
predetermined area around a mobile unit, such as the host vehicle,
earliest among courses along which the other object can travel.
Thus, it is possible to further desirably prevent interference
between the mobile unit and the other object. The maximum speed of
the other object may be, for example, prestored in form of a
database in accordance with the type of other object.
[0066] Furthermore, in the above embodiment, the three estimated
courses P1 to P3 are generated as the first courses on the basis of
information of a shape, or the like, of a road around the host
vehicle; instead, the first courses may be generated on the basis
of another condition. For example, the first courses may be
generated on the basis of a condition that "the host vehicle
travels in the middle of a road at a speed limit". When the first
courses are generated on the basis of the above condition, the host
vehicle may travel at a speed limit as much as possible, and, when
the host vehicle is likely to interfere with another object, the
host vehicle may avoid interference in accordance with braking
courses. Thus, the host vehicle is able to travel at a high driving
efficiency around a speed limit not exceeding the speed limit and
is able to avoid interference with another object.
* * * * *